Barbatula

Chen, Hao, Zhang, Hui, Chen, Yongxia & Freyhof, Jörg, 2019, A review of the Barbatula loaches (Teleostei: Nemacheilidae) from north-eastern China, with the description of four new species, Zootaxa 4565 (1), pp. 1-36 : 6

Key to species of Barbatula in north-eastern China

1a. Anterior and posterior nostril widely spaced; lower lip with lateral expansion...................................... 2

1b. Anterior and posterior nostril closely set; lower lip without lateral expansion...................................... 8

2a. 6½ branched dorsal-fin rays; pelvic-fin origin in front of vertical through dorsal-fin origin................ B. potaninorum

2b. 7½ branched dorsal-fin rays; pelvic-fin origin below or behind vertical through dorsal-fin origin....................... 3

3a. Scales restricted to flank and back behind dorsal-fin origin..................................................... 4

3b. Scales present on complete flank and back, scales often isolated from each other and deeply embedded.................. 6

4a. Dorsal profile convex; scales restricted to caudal peduncle.......................................... B. pechiliensis

4b. Dorsal profile slightly convex; scales present on flank and back behind dorsal-fin origin............................. 5

5a. Snout blunt; pelvic-fin origin situated below the vertical through the dorsal-fin origin; median incision in upper lip longer than 50% of width of upper lip......................................................................... B. gibba

5b. Snout pointed; pelvic-fin origin situated behind the vertical through the dorsal-fin origin; median incision in upper lip less than 20% of width of upper lip................................................................... B. zhangwuensis

6a. Snout length equal to postorbital head length; dorsal profile convex.......................................... B. toni

6b. Snout length shorter than postorbital head length; dorsal profile slightly convex.................................... 7

7a. Scales present on back anterior to dorsal-fin origin; mental lobe without expansion......................... B. kirinensis

7b. Scales absent on back anterior to dorsal-fin origin; mental lobe with blade-shaped expansion.............. B. liaoyangensis

8a. Scales restricted to flank and back behind last dorsal-fin ray............................................... B. nuda

8b. Scales present from flank anterior to dorsal-fin origin to caudal peduncle, scales often isolated and embedded............ 9

9a. Median incision in upper lip less than 30% of width of upper lip; snout length equal to postorbital head length; pelvic-fin origin situated below the vertical through the dorsal-fin origin........................................... B. linjiangensis

9b. Median incision in upper lip longer than 40% of width of upper lip; snout length shorter than postorbital head length; pelvic-fin origin situated in front of the vertical through the dorsal-fin origin...................................... B. emuensis